MACK Recalls

Oct 11, 1978 – A SHORT CIRCUIT COULD OCCUR DUE TO CHAFING OR WIRE DISCONNECTION IN THE BOX.

Oct 03, 1978 – DELAYS OF UP TO ABOUT 2 SECONDS MAY EXIST IN THE BRAKE APPLICATION TIMES TO THE BRAKES ON THE BOGIE AXLES IN THE PRESENCE OF CERTAIN TYPES OF WHEEL SPEED SENSOR SIGNAL DISCONTINUITIES OR DISTORTIONS THAT MAY OCCUR AS A RESULT OF SENSOR WIRE FAILURE. THIS CONSTITUTES A NON-COMPLIANCE TO FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 121, "AIR BRAKE SYSTEMS".

Aug 08, 1978 – THE POSSIBILITY EXISTS THAT THE ALUMINUM ENGINE REAR SUPPORT BRACKETS MAY FAIL DUE TO METAL FATIGUE. THIS TYPE OF FAILURE WOULD ALLOW THE ENGINE AND TRANSMISSION ASSEMBLY TO DISLOCATE DOWNWARD. THIS WILL RESULT IN THROTTLE CONTROL LOSS WITH THE ENGINE OPERATING CONTINUOUSLY IN THE MID TO UPPER RANGE OF THE GOVERNED SPEED RANGE.

Aug 08, 1978 – DEFICIENCIES, IN THE FORM OF FORGING LAPS, CRACKS AND EXCESSIVE DECARBURIZATION DURING HEAT TREATMENT, EXIST IN THE STEERING KNUCKLES. STRESSES IMPOSED WITH INTEGRAL HYDRAULIC POWER STEERING MAY LEAD TO A FAILURE IN THE AREA OF THE STEERING ARM ATTACHING BOSS. THIS TYPE OF FAILURE WOULD CAUSE LOSS OF STEERING CONTROL.

Aug 08, 1978 – THE EXISTING CROSS STEERING ARMS MAY HAVE INSUFFICIENT FATIGUE LIFE IN THE NECK AREA. THIS IS NEAR THE BOSS FOR THE CROSS STEERING TUBE BALL JOINT CONNECTION. FAILURE OF EITHER OF THE CROSS STEERING LEVERS COULD LEAD TO LOSS OF STEERING CONTROL OF THE RIGHT FRONT WHEEL.

Aug 07, 1978 – THE ALUMINUM FRONT SPRING BRACKET IS DEFECTIVE IN THAT IT MAY SHEAR AT THE POINT OF FRAME RAIL ATTACHMENT. THIS SHEARING COULD DISLOCATE THE STEERING AXLE.

Apr 04, 1978 – AN AXLE "NO BRAKE" CONDITION COULD RESULT FROM AN EATON CONTROLLER INTERNAL ELECTRICAL MALFUNCTION. THIS CONDITION MAY CAUSE THE ANTI-WHEEL LOCK VALVE SOLENOID TO BE CONTINUOUSLY ENERGIZED AND PREVENT THE BRAKES FROM BEING APPLIED ON ONE OF THE AXLES. AS A RESULT, THE ANTI-WHEEL LOCK WARNING LAMP IS NOT ACTIVATED.

Feb 09, 1978 – THE STEERING PITMAN ARM IS SUBJECT TO FAILURE AT THE AREA OF THE TRANSITION TO THE ARM OFFSET DUE TO HIGH STRESS CONCENTRATIONS.

Feb 09, 1978 – THE AIR RESERVOIR ON THE INVOLVED VEHICLES MAY HAVE A DESIGN DEFICIENCY. THE RESERVOIR MAY NOT BE STRONG ENOUGH TO WITHSTAND PRESSURES GENERATED DURING OPERATION.

Feb 09, 1978 – A DESIGN DEFICIENCY EXISTS IN THE AIR DRYER PIPING IN THE AREA OF THE PRESSURE RELIEF VALVE AND COMPRESSOR GOVERNOR CONTROL LINK. MOISTURE IS PASSED AND BUILDS UP IN THIS RELIEF VALVE AND CONTROL LINE. IN FREEZING AMBIENT TEMPERATURES, THIS MOISTURE MAY FREEZE, ALLOWING THE CHASSIS AIR SYSTEM PRESSURE TO EXCEED 150 PSI. EXCESSIVE AIR SYSTEM PRESSURE CAN CAUSE SEPARATION OF AIR PIPING CONNECTIONS AND AIR SYSTEM VALVE FAILURE.